Honestly?
http://en.wikipedia.org/wiki/Square_wave
Short distance down on the right. I know they can be part of some really cool sounds, but alone? That's barely a step above "Fingernails on chalkboard" to my ears.
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Can't blow a speaker by under powering it.......
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http://en.wikipedia.org/wiki/Square_wave
Short distance down on the right. I know they can be part of some really cool sounds, but alone? That's barely a step above "Fingernails on chalkboard" to my ears.
Mr. Foxen
Commercial User
Luckily its impossible for amps to produce square waves, because square waves require infinite bandwidth.
Mr. Foxen
Commercial User
A sine is just a square with the corners cut off. Which incidentally is what happens when you put them into an inductive or capacitive load. Like a speaker, or crossover.
Amplifiers also cannot reproduce a perfect sine wave.... due to various added distortions, however slight.
Such is the nature of picking nits....
Headphones can do a good job of reproducing a square wave
Yes, there's overshoot, but even at 300 hz it settles down.
And I've seen audiophiles boast about their square wave response even posting scope traces
Can't see how these systems could possible get so close.
Yes, there's overshoot, but even at 300 hz it settles down.
And I've seen audiophiles boast about their square wave response even posting scope traces
Can't see how these systems could possible get so close.
The thing is though, a DC offset is a far, far different thing from all the other babble about the cones "stopping" when they hit the "DC part" (clipped top) of an AC wave. Most of the comments about DC are founded on a notion that the flat tops of a clipped wave are DC, and therefore it's just like plugging a car battery in to the speaker, and the speaker slams to a halt.
Well, it may "slam to a halt" if it hits some Xmax limiting obstruction, due to being driven at a frequency below (or just above, in a bad design) box/port resonance, etc......
However, current determines force pushing the cone in a speaker. if the air load is dominant, there is one reaction to a square wave, if the suspension is dominant, there is a different one. Since any current pushes only so hard, and the suspension is similar to a spring, the suspension limited movement might positionally look like a square wave (the air movement would be "differentiated").
if the speaker is well air loaded, it will move during the "flat top" time, pushing with a constant force on the air load
Cerwin-Vega were famous for asserting they were the only ones who could reproduce a square wave..... I don't recall anymore just what they claimed..
The infinite bandwidth requirement means that nothing can produce square waves. In the real world we have to be a bit less pedantic.
Mr. Foxen
Commercial User
Should probably stop referencing square waves, since clipped amps don't make them, so they are pretty irrelevant.
Headphones can do a good job of reproducing a square wave
Yes, there's overshoot, but even at 300 hz it settles down.
And I've seen audiophiles boast about their square wave response even posting scope traces
Can't see how these systems could possible get so close.
FWIW it's my understanding that the inaccuracies in transducers when reproducing a square wave are a combination of frequency response and phase anomalies. Check out these Shures with a 50 Hz square wave http://www.headphone.com/headphones/shure-srh240-a.php#tabs
Bob Lee (QSC)
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And the nature of the enclosure. For instance it generally will NOT BE TRUE of a driver in a proper horn-loaded LF enclosure, driven within its limits of frequency.... The cone is very effectively loaded and moves very little.
In an "acoustic suspension" (sealed box) enclosure, it may be very true at LF.....
generalizations totally fail in a subject with as much diversity of approaches as is present with speakers...... which is a nifty generalization of dubious merit.
I'm glad I asked for a SIMPLE way to explain this. Oy.
Sorry guys. I didn't mean to reopen old wounds. I had accepted the premise. I just wanted some easy to understand language to help me and the other guy wrap our heads around it. One thing is for sure. There are lots of high IQ's around here (even if they tend to disagree).
Sorry guys. I didn't mean to reopen old wounds. I had accepted the premise. I just wanted some easy to understand language to help me and the other guy wrap our heads around it. One thing is for sure. There are lots of high IQ's around here (even if they tend to disagree).
It is very hard to break a 1 gallon container (speaker cab) by pouring 1/2 gallon of liquid into it (amplifier wattage).
It's all good. There's nothing like an underpowering/clipping thread to get the amps forum all hot and bothered.
Did my post #123 have anything helpful for you in it?
http://www.talkbass.com/forum/f15/cant-blow-speaker-under-powering-918512/index7.html#post13212459
Oh?.........
That certainly varies...... depends "how clipped" the signal is..... you do get "squared-off sine waves", which audibly are not a lot different, and already have a higher rms value than unclipped of same peak level.
Most folks won't get far into clipping, since it tends not to sound so good, unless filtered as with a synth.
"Lucky Man", eh..... that and a lot of Pink Floyd, some Soft Machine, etc, etc,..... Synth was big in that way back when it was a "new" sound..... now it's whatever.............
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